Cressida Dick, the Metropolitan police commissioner: ‘It is having a massive strain on our people and it cannot go on.’
Photograph: Simon Dawson/Reuters

The three most senior police officers in England and Wales have expressed concerns that funding cuts and pressure on resources are hampering their ability to tackle serious crime.

Appearing before the home affairs select committee, Cressida Dick, the Metropolitan police commissioner; Lynne Owens, the director general of the National Crime Agency; and Sara Thornton, the National Police Chiefs’ Council chairwoman, gave examples of how cash shortages were posing a risk to public safety.

Dick said it would be “naive” to suggest reductions in police officers was having no impact on rising crime. She added: “It is having a massive strain on our people and it cannot go on. We are in the middle of the largest change programme the Met has ever been through. It cannot go on without hard choices – either more money, smaller mission, greater risk of attack.”

Owens said: “The whole system needs a different approach to funding to make sure we are as good as we all want us to be.”

Thornton added: “There is undoubtedly a capacity issue in neighbourhood policing ... it does need some extra investment.”

Asked to state their biggest concern, all three highlighted the challenge posed by the rise in digital data and cybercrime.

The amount of data that Met officers have to deal with doubles every 18 months, Dick said. She admitted that officers were struggling with the extra workload.

She said it was not unusual for 18 officers to work 200 hours over a weekend to trawl through Facebook accounts to ensure that a trial was fair with regard to disclosure.

Thornton said the reduction in the number of sexual offence cases reaching court in the last two years suggested resources were being overstretched.

She said: “There is cause for concern. It is resource-intensive. We are shifting people. I am concerned about how many cases might be caught in the system.”

She added: “We are 17% down on the number of detectives we’d like in an ideal world, so we are trying to push resources into an area where we are already short.”

The chair of the committee, Yvette Cooper, asked Dick to give a single message to the home secretary, Sajid Javid. Dick said: “Support my people. They need to be well-led, they need to be well-equipped, they do need to be well-resourced and they need to have a public who feel confident. They need to be given the benefit of the doubt when things go wrong and not have point finger of blame.”

She also urged the Home Office to show greater trust in police officers. She said: “It sometimes feels like there is not much central push, it’s kind of ‘get on with it, good luck’, but at the same time it has felt a bit parent-child. We are in this together for our public and we would love to work ever more closely with the Home Office so that they feel even more confident in us and they can project that to others.”

Dick, Owens and Thornton also claimed the way English and Welsh policing was organised into 43 separate forces was hampering coordination on national crime issues.

Thornton said: “If you did a poll of chief constables, most would say for operational reasons it would make sense to have a fewer number of larger forces. But the issue is political. We are constantly trying get people to collaborate to cooperate in the public interest. We are making progress. Sometimes the progress is glacial.”

Owens said she was concerned forces were “going to be get left behind” on national issues such as cybercrime, fraud and child sexual abuse, because of the current division of forces.

Labour seized on the officers’ concerns over resourcing. Louise Haigh, the shadow policing minister, said: “The most senior police officers in the land have called out the dangerous Tory delusion on police cuts.

“In the face of overwhelming evidence from senior officers and their own officials, it appears that the only people in the country who now believe the loss of 21,000 officers hasn’t made the blindest bit of difference to community safety is Theresa May’s government.”